>Sometimes I'm shocked at how cavalier some people can be about managementI find this attitude especially prevalent in the tech startup end of things for a few reasons: Most startups start small enough that peer-to-peer relationships and a personal stake & passion all mean that having staff in a role solely dedicated to managerial work isn't necessary. As a result of this, when they get larger, they undervalue the need. As a result of that, as the need arises, it is poorly done, furthering the sentiment that such roles are wasteful of resources and time.
Outside of this "home grown" disdain for managers in tech, there's also the problem systemic in modern business stemming from the idea of "scientific management" that arose about 100 years ago and really gained traction in the 50's & 60's. Depending on your point of view, it's either fundamentally wrong (in part or whole), or it has simply been poorly implemented in nearly all cases. Regardless, it's what gave rise to the notion that "manager" was a job like any trade, and people could be trained up and deployed as interchangeable pieces in any business. (Which rather ignored the fact that even in trades, there are specialties). It created a few generations of managers that thought actual detailed knowledge of a business's operations wasn't necessary to being a good manager.
I think we're, mostly, past that. (as in past the tipping point moving away from it, not that it isn't still prevalent in some segments of business)
But the two phenomena are where I think the casual disdain comes from in the tech industry for non-engineering managers.